Humidity controller

ABSTRACT

A humidity controller apparatus ( 10 ) includes a refrigerant circuit provided with first and second heat exchangers ( 61, 62 ). An adsorbent is supported on the surface of each of the first and second heat exchangers ( 61, 62 ). The refrigerant circuit is configured to allow for switching of the circulation direction of a refrigerant by operation of a four-way selector valve. In addition, in the humidity controller apparatus ( 10 ), a switching mechanism ( 50 ) switches the distribution routes of air streams. The humidity controller apparatus ( 10 ) operates the four-way selector valve and the switching mechanism ( 50 ), whereby a first air stream is dehumidified in the heat exchanger ( 61 ) or ( 62 ), whichever is acting as an evaporator while, on the other hand, a second air stream is humidified in the heat exchanger ( 61 ) or ( 62 ), whichever is acting as a condenser. In the humidity controller apparatus ( 10 ), the operation of the refrigerant circuit and the switching time interval of the air stream distribution routes are set depending on the load of humidity control. As the humidity control load increases, the switching time interval is set smaller.

TECHNICAL FIELD

The present invention relates to humidity controller apparatuses whichoperate to regulate the humidity of air, and it relates morespecifically to a humidity controller apparatus which performs aso-called batch running operation.

BACKGROUND ART

Humidity controller apparatuses for regulating the humidity of air bymaking utilization of an adsorbent and a refrigeration cycle have beenknown in the prior art. One such humidity controller apparatus isdisclosed in for example Japanese Patent Application Publication (Kokai)No. 1996-189667. The humidity controller apparatus is so configured asto perform a so-called batch running operation.

The above-mentioned humidity controller apparatus includes twoadsorption units. Each adsorption unit is made up of a mesh receptaclefilled with an adsorbent and a refrigerant pipe extending through themesh receptacle. The refrigerant pipe of each adsorption unit is influid connection with a refrigerant circuit which performs arefrigeration cycle. In addition, the humidity controller apparatus isprovided with dampers for switching of the routes of air streams whichare delivered, respectively, to the adsorption units.

When the above-descried humidity controller apparatus is in operation,the compressor of the refrigerant circuit is operated to perform arefrigeration cycle in which one of the two adsorption units acts as anevaporator while the other adsorption unit acts as a condenser. Inaddition, a four-way selector valve in the refrigerant circuit isoperated to allow for switching of the direction in which therefrigerant is circulated and, as a result, each adsorption unitfunctions alternately as an evaporator and as a condenser.

When the humidity controller apparatus is in a humidification mode ofoperation, a stream of supply air flowing from outside a room to insidethe room is introduced into one adsorption unit that becomes acondenser. The supply air stream is humidified by moisture desorbed fromthe adsorbent. At that time, a stream of exhaust air flowing from insidethe room to outside the room is introduced into the other adsorptionunit that becomes an evaporator. Moisture present in the exhaust airstream is collected by the adsorbent. On the other hand, when thehumidity controller apparatus is in a dehumidification mode ofoperation, a stream of supply air flowing from outside the room toinside the room is introduced into one adsorption unit that becomes anevaporator. Moisture present in the supply air stream is adsorbed on theadsorbent. At that time, a stream of exhaust air flowing from inside theroom to outside the room is introduced into the other adsorption unitthat becomes a condenser. Moisture desorbed from the adsorbent isdischarged to outside the room, together with the exhaust air stream.

In addition, as a means having the same function as the above-describedadsorption units, a heat exchange member, as disclosed in for exampleJapanese Patent Application Publication (Kokai) No. 1995-265649, hasbeen known in the art. In the heat exchange member, plate-like fins arearranged around a copper pipe and an adsorbent is supported on thesurface of the copper pipe and the surface of each fin. And, the heatexchange member is so configured as to effect heating and cooling of theadsorbent by a fluid flowing through the copper pipe.

In addition, a humidity controller apparatus which performs a batchrunning operation, as disclosed in for example Japanese PatentApplication Publication (Kokai) No. 2003-28458, has been known in theart. The humidity controller apparatus has two adsorption elements,wherein many air flow paths are formed in each adsorption element. Whena first air stream is dehumidified in the first adsorption element, asecond air stream heated in a condenser of a heat pump is delivered tothe second adsorption element so that the adsorbent is regenerated. Onthe other hand, when a first air stream is dehumidified in the secondadsorption element, a heated second air stream is delivered to the firstadsorption element so that the adsorbent is regenerated. The humiditycontroller apparatus alternately repeatedly performs the above-describedtwo operations, thereby to supply either a dehumidified first air streamor a humidified second air stream to an indoor space.

PROBLEMS THAT INVENTION INTENDS TO SOLVE

The problem with the above-described prior art humidity controllerapparatuses is that no consideration is made at all on adjustment of thecapability to control the humidity. This gives rise to the possibilitythat, for the indoor latent heat load, an excess or deficiency in thehumidity control capability of the humidity controlling apparatusoccurs. As a result, comfortable indoor conditions may not be providedsufficiently and, in addition, energy savings in the humidity controllerapparatus may not be accomplished sufficiently either.

With the above-described problems in mind, the present invention wasmade. Accordingly, an object of the present invention is to enable, in ahumidity controller apparatus which performs a so-called batch runningoperation, adjustment of the humidity control capability of the humiditycontroller apparatus for the purpose of assuring comfort andaccomplishing energy savings of the humidity controller apparatus.

DISCLOSURE OF THE INVENTION

A first invention is directed to a humidity controller apparatus whichtakes in a first air stream and a second air stream and supplies to anindoor space either the first air stream dehumidified or the second airstream humidified. In the humidity controller apparatus of the firstinvention: the humidity controller apparatus comprises a firstadsorption unit (61) and a second adsorption unit (62), each of thefirst and second adsorption units (61, 62) having a respective adsorbentwhich is brought into contact with air; the humidity controllerapparatus is configured to perform, repeatedly alternately at apredetermined switching time interval, a first operation in which thesecond air stream is humidified as a result of regeneration of theadsorbent of the first adsorption unit (61) while, simultaneously, thefirst air stream is dehumidified in the second adsorption unit (62) anda second operation in which the second air stream is humidified as aresult of regeneration of the adsorbent of the second adsorption unit(62) while, simultaneously, the first air stream is dehumidified in thefirst adsorption unit (61); and the humidity controller apparatus isprovided with an interval set means (74) for setting the predeterminedswitching time interval depending on the load of the humidity controllerapparatus.

A second invention according to the first invention is provided in whichthe interval set means (74) is configured to set the predeterminedswitching time interval such that the set value of the predeterminedswitching time interval decreases as the load of the humidity controllerapparatus increases.

A third invention according to the first or second invention is providedin which: the humidity controller apparatus comprises a refrigerantcircuit (60) in which a plurality of heat exchangers (61, 62) eachsupporting on its surface a respective adsorbent are connected, therefrigerant circuit (60) allowing for switching between a firstrefrigeration cycle operation in which the first heat exchanger (61)becomes a condenser while the second heat exchanger (62) becomes anevaporator and a second refrigeration cycle operation in which thesecond heat exchanger (62) becomes a condenser while the first heatexchanger (61) becomes an evaporator; and the refrigerant circuit (60)performs a first refrigeration cycle operation during the firstoperation while, on the other hand, the refrigerant circuit (60)performs a second refrigeration cycle operation during the secondoperation, and the first heat exchanger (61) and the second heatexchanger (62) constitute, respectively, a first adsorption unit and asecond adsorption unit.

A fourth invention according to the third invention is provided in whichthe humidity controller apparatus comprises: a switching mechanism (50)for switching of the distribution routes of the first and second airstreams in response to interswitching between the first operation andthe second operation; and a switching control means (73) for performinga control operation so that the switching mechanism (50) preswitches thedistribution routes of air streams a predetermined length of time aheadof switching of the operation of the refrigerant circuit (60), when thesecond air stream has a higher temperature than the first air stream onthe upstream side of the heat exchangers (61, 62).

A fifth invention according to the third invention is provided in whichthe humidity controller apparatus comprises: a switching mechanism (50)for switching of the distribution routes of the first and second airstreams in response to interswitching between the first operation andthe second operation; and a switching control means (73) for performinga control operation so that the switching mechanism (50) switches thedistribution routes of air streams after an elapse of a predeterminedlength of time since switching of the operation of the refrigerantcircuit (60), when the first air stream has a higher temperature thanthe second air stream on the upstream side of the heat exchangers (61,62).

A sixth invention according to the third invention is provided in which:a compressor (63), disposed in the refrigerant circuit (60), isconfigured to be variable in capacity; and a capacity control means (71)is provided which varies the capacity of the compressor (63) at the samecycle as the cycle at which the operation of the refrigerant circuit(60) is switched.

A seventh invention according to the third invention is provided inwhich: a refrigerant expansion mechanism, disposed in the refrigerantcircuit (60), is formed by an expansion valve (65) which is variable inopening; and an opening control means (72) is provided which varies theopening of the expansion valve (65) at the same cycle as the cycle atwhich the operation of the refrigerant circuit (60) is switched.

WORKING OPERATION

In the first invention, the first operation and the second operation arecarried out in an interswitching manner. Interswitching between thefirst operation and the second operation is made periodically atintervals of a predetermined switching time. In the humidity controllerapparatus (10) of the first invention, during the first operation, asecond air stream is delivered to the first adsorption unit (61) and afirst air stream is delivered to the second adsorption unit (62). In thefirst adsorption unit (61), the adsorbent is regenerated, and the secondair stream is humidified by moisture desorbed from the adsorbent. Inaddition, in the second adsorption unit (62), moisture present in thefirst air stream is adsorbed on the adsorbent and, as a result, thefirst air stream is dehumidified. On the other hand, during the secondoperation, a first air stream is delivered to the first adsorption unit(61) and a second air stream is delivered to the second adsorption unit(62). In the first adsorption unit (61), moisture present in the firstair stream is adsorbed on the adsorbent and, as a result, the first airstream is dehumidified. In the second adsorption unit (62), theadsorbent is regenerated, and the second air stream is humidified bymoisture desorbed from the adsorbent.

In the first invention, the humidity controller apparatus (10) supplieseither a dehumidified first air stream or a humidified second air streamto an indoor space. In other words, the humidity controller apparatus(10) may be configured so as to supply only a dehumidified first airstream (or only a humidified second air stream) into the room. Inaddition, the humidity controller apparatus (10) may be configured so asto operate switchably between a first mode of operation in which adehumidified first air stream is supplied into an indoor space and asecond mode of operation in which a humidified second air stream issupplied into the indoor space.

Furthermore, in the first invention, the humidity controller apparatus(10) is provided with the interval set means (74). The interval setmeans (74) sets switching time intervals depending on the load of thehumidity controller apparatus (10). In the humidity controller apparatus(10), interswitching between the first operation and the secondoperation is made at a switching time interval established by theinterval set means (74). The interval set means (74) makes an adjustmentin the switching time interval, whereby the capability to control thehumidity obtained in the humidity controller apparatus (10) is adjusteddepending on the load of the humidity controller apparatus (10). Statedanother way, as the switching time interval at which interswitchingbetween the first and second operations is made is varied, the amount ofdehumidification from the first air stream and the amount ofhumidification to the second air stream vary, and the humidity controlcapability of the humidity controller apparatus (10) varies.

In the second invention, the switching time interval is set shorter bythe interval set means (74), as the load of the humidity controllerapparatus (10) becomes greater. Here, in the humidity controllerapparatus (10) which alternately selectively performs a first operationand a second operation, moisture adsorption/desorption for the adsorbentof the adsorption unit takes places intensively within a relativelyshort period of time after interswitching between the two operations.For example, with regard to moisture which is desorbed from theadsorbent of the first adsorption unit (61) during the first operation,most of the moisture will have been desorbed from the adsorbent shortlyafter the start of the first operation. In addition, with regard tomoisture which is adsorbed on the adsorbent of the second adsorptionunit (62) during the first operation, most of the moisture will havebeen adsorbed on the adsorbent shortly after the start of the firstoperation.

If the switching time interval is set longer to extend the time forwhich the first and second operations continue, this prolongs the periodduring which there occurs little moisture adsorption/desorption for theadsorbents. As a result, the humidity control capability of the humiditycontroller apparatus (10) falls. On the contrary, if the switching timeinterval is set shorter to reduce the time for which the first andsecond operations continue, this increases the frequency at whichmoisture adsorption/desorption for the adsorbents takes placeintensively. As a result, the humidity control capability of thehumidity controller apparatus (10) increases.

Therefore, the interval set means (74) is provided to set a switchingtime interval in the second invention, as described above, and thehumidity control capability of the humidity controller apparatus (10) isincreased or decreased proportionally to the increase and decrease inthe load of the humidity controller apparatus (10).

In the third invention, two different refrigeration cycle operations arerepeatedly carried out in alternation manner in the refrigerant circuit(60). In addition, the switching mechanism (50) switches thedistribution routes of the first and second air streams in response toswitching of the operation of the refrigerant circuit (60).

In the refrigerant circuit (60) of the third invention, during the firstrefrigeration cycle operation a second air stream is delivered to thefirst heat exchanger (61) which becomes a condenser while, on the otherhand, a first air stream is delivered to the second heat exchanger (62)which becomes an evaporator. In the first heat exchanger (61), theadsorbent is regenerated as a result of heating by the refrigerant anddesorbed moisture from the adsorbent is given to the second air stream.In addition, in the second heat exchanger (62), moisture present in thefirst air stream is adsorbed on the adsorbent and heat of adsorptiongenerated at that time is absorbed by the refrigerant. On the otherhand, during the second refrigeration cycle operation, a first airstream is delivered to the first heat exchanger (61) which becomes anevaporator while, on the other hand, a second air stream is delivered tothe second heat exchanger (62) which becomes a condenser. In the firstheat exchanger (61), moisture present in the first air stream isadsorbed on the adsorbent and heat of adsorption generated at that timeis absorbed by the refrigerant. On the other hand, in the second heatexchanger (62), the adsorbent is regenerated as a result of heating bythe refrigerant and desorbed moisture from the refrigerant is given tothe second air stream.

In the fourth invention, the switching control means (73) of thehumidity controller apparatus (10) controls the switching mechanism (50)so that the distribution routes of air streams are switched prior toswitching of the operation of the refrigerant circuit (60). Such acontrol operation of the switching control means (73) is carried out ifthe second air stream has a higher temperature than the first air streambefore passage through the heat exchangers (61, 62).

Suppose here that a second air stream is delivered to the first heatexchanger (61) acting as a condenser while a first air stream isdelivered to the second heat exchanger (62) acting as an evaporator. Inthis state, in the invention as set forth in claim 4, the airdistribution routes are switched. As a result, the first air stream isdelivered to the first heat exchanger (61) and the second air stream isdelivered to the second heat exchanger (62). After an elapse of apredetermined length of time since then, the refrigeration cycleoperation of the refrigerant circuit (60) is switched.

Consequently, the first air stream of lower temperature than thepreviously-delivered second air stream is delivered to the first heatexchanger (61) converting from a condenser to an evaporator. As aresult, the adsorbent disposed in the first heat exchanger (61) isprecooled by the first air stream before the first heat exchanger (61)converts into an evaporator. On the other hand, the second air stream ofhigher temperature than the previously-delivered first air stream isdelivered to the second heat exchanger (62) converting from anevaporator to a condenser. As a result, the adsorbent disposed in thesecond heat exchanger (62) is preheated by the second air stream beforethe second heat exchanger (62) converts into a condenser.

In the fifth invention, the switching control means (73) of the humiditycontroller apparatus (10) controls the switching mechanism (50) so thatthe distribution routes of air streams are switched after switching ofthe operation of the refrigerant circuit (60). Such a control operationof the switching control means (73) is carried out if the first airstream has a higher temperature than the second air stream beforepassage through the heat exchangers (61, 62).

Suppose here that a second air stream is delivered to the first heatexchanger (61) acting as a condenser while a first air stream isdelivered to the second heat exchanger (62) acting as an evaporator. Inthis state, in the invention as set forth in claim 5, the refrigerationcycle operation of the refrigerant circuit (60) is switched with the airdistribution routes held unchanged. After an elapse of a predeterminedlength of time since then, the air distribution routes are switched.

Consequently, the second air stream having a lower temperature than thefirst air stream is continuously supplied to the first heat exchanger(61) which has converted to an evaporator from a condenser for apredetermined length of time. And, the adsorbent disposed in the firstheat exchanger (61) is cooled by both the refrigerant of the refrigerantcircuit (60) and the second air stream and, thereafter, comes intocontact with the first air stream. On the other hand, the first airstream having a higher temperature than the second air stream iscontinuously supplied to the second heat exchanger (62) which hasconverted to a condenser from an evaporator for a predetermined lengthof time. And, the adsorbent disposed in the second heat exchanger (62)is heated by both the refrigerant of the refrigerant circuit (60) andthe first air stream and, thereafter, comes into contact with the secondair stream.

In the sixth invention, the compressor (63) of the refrigerant circuit(60) is variable in capacity. The capacity of the compressor (63) iscontrolled by the capacity control means (71). The capacity controlmeans (71) periodically increases and decreases the capacity of thecompressor (63). The cycle at which the capacity of the compressor (63)is varied by the capacity control means (71) is the same as the cycle atwhich the refrigeration cycle operation of the refrigerant circuit (60)is switched. In other words, the capacity of the compressor (63) isadjusted regularly in response to switching of the refrigeration cycleoperation of the refrigerant circuit (60).

As a specific constructional example of the capacity control means (71)in the sixth invention, there are two examples as described below.

A first constructional example of the capacity control means (71) in thesixth invention is a means which performs, every time the operation ofthe refrigerant circuit (60) is switched, a control operation oftemporarily pre-decreasing the capacity of the compressor (63) prior toswitching of the operation of the refrigerant circuit (60) and thenincreasing the capacity of the compressor (63) upon the switching of theoperation of the refrigerant circuit (60).

In the first constructional example, the capacity control means (71)performs a predefined control operation every time the refrigerationcycle operation of the refrigerant circuit (60) is switched. In thiscontrol operation, the capacity control means (71) reduces in advancethe capacity of the compressor (63) at the time of switching of theoperation of the refrigerant circuit (60). To sum up, the refrigerationcycle operation of the refrigerant circuit (60) is switched with thecapacity of the compressor (63) temporarily reduced. And, when therefrigeration cycle operation of the refrigerant circuit (60) isswitched, the capacity control means (71) increases the once-reducedcapacity of the compressor (63).

As described above, when the humidity controller apparatus (10) is inoperation, moisture present in the air is adsorbed on the adsorbent of aheat exchanger (61, 62) which becomes an evaporator and moisture isdesorbed out of the adsorbent of another heat exchanger (61, 62) whichbecomes a condenser. And, when approaching the point just before theoccurrence of switching of the refrigeration cycle operation of therefrigerant circuit (60), the adsorbent will no longer adsorb moisturevery much even when the heat exchanger (61, 62) which becomes anevaporator is continuously cooled and, in addition, moisture is nolonger desorbed very much from the adsorbent even when the heatexchanger (61, 62) which becomes a condenser is continuously heated.That is to say, even if the compressor (63) is continuously operated atgreat capacity until the time just before switching of the refrigerationcycle operation of the refrigerant circuit (60), the effects ofsufficiently increasing the amount of dehumidification from the firstair stream and the amount of humidification to the second air stream arenot expected any more.

To cope with the above, in the first constructional example of thecapacity control means (71) in the sixth invention, the capacity controlmeans (71) reduces the capacity of the compressor (63) in order to cutdown, for example, electric power necessary for operating the compressor(63) at the stage slightly before switching of the operation of therefrigerant circuit (60) where the amount of dehumidification and theamount of humidification are already unlikely to increase. In addition,if the capacity of the compressor (63) decreases before switching of theoperation of the refrigerant circuit (60), the capability to heatadsorbent and the capability to cool adsorbent are loweredproportionally. This makes it possible to reduce the time from when therefrigeration cycle operation of the refrigerant circuit (60) isswitched to when the adsorbent reaches a temperature capable of allowingthe adsorbent to effect sufficient moisture adsorption/desorption. As aresult, the humidity control capability of the humidity controllerapparatus (10) is improved.

A second constructional example of the capacity control means (71) inthe sixth invention is a means which performs, every time the operationof the refrigerant circuit (60) is switched, a control operation oftemporarily increasing the capacity of the compressor (63) above areference capacity corresponding to the load of the humidity controllerapparatus immediately after switching of the operation of therefrigerant circuit (60) and then decreasing the capacity of thecompressor (63) after an elapse of a predetermined length of time sincethe switching of the operation of the refrigerant circuit (60).

In the second constructional example, the capacity control means (71)performs a predefined control operation every time the refrigerationcycle operation of the refrigerant circuit (60) is switched. In thiscontrol operation, the capacity control means (71) temporarily increasesthe capacity of the compressor (63) upon switching of the refrigerationcycle operation of the refrigerant circuit (60). At that time, thecapacity control means (71) increases the capacity of the compressor(63) to exceed the reference capacity corresponding to the load of thehumidity controller apparatus (10). Then, after an elapse of apredetermined length of time since the switching of the refrigerationcycle operation of the refrigerant circuit (60), the capacity controlmeans (71) reduces the once-increased capacity of the compressor (63).

To sum up, in the second constructional example of the capacity controlmeans (71) in the sixth invention, the capacity control means (71)temporarily increases the capacity of the compressor at the stage justafter switching of the refrigeration cycle operation of the refrigerantcircuit (60) where the adsorbents are required to be heated and cooledrapidly. Consequently, the temperature of the adsorbent in the heatexchanger (61, 62) which has converted into a condenser is increasedrapidly, thereby making it possible to secure the amount ofhumidification to an air stream and, on the other hand, the temperatureof the adsorbent in the heat exchanger (61, 62) which has converted intoan evaporator is lowered rapidly, thereby making it possible to securethe amount of dehumidification from an air stream.

In the seventh invention, the expansion valve (65) which is variable inopening is provided to act as a refrigerant expansion mechanism in therefrigerant circuit (60). The opening of the expansion valve (65) iscontrolled by the opening control means (72). The opening control means(72) periodically increases and decreases the opening of the expansionvalve (65). The cycle, at which the opening of the expansion valve (65)is varied by the opening control means (72), is the same as the cycle atwhich the refrigeration cycle operation of the refrigerant circuit (60)is switched. In other words, the refrigeration cycle operation of therefrigerant circuit (60).

As a specific constructional example of the opening control means (72)in the seventh invention, there are two examples as described below.

A first constructional example of the opening control means (72) in theseventh invention is a means which performs, every time the operation ofthe refrigerant circuit (60) is switched, a control operation oftemporarily pre-increasing the opening of the expansion valve (65) priorto switching of the operation of the refrigerant circuit (60) and thendecreasing the opening of the expansion valve (65) upon the switching ofthe operation of the refrigerant circuit (60).

In the first constructional example, the opening control means (72)performs a predefined control operation every time the refrigerationcycle operation of the refrigerant circuit (60) is switched. In thiscontrol operation, the opening control means (72) increases in advancethe opening of the expansion valve (65) at the time of switching of theoperation of the refrigerant circuit (60). To sum up, the refrigerationcycle operation of the refrigerant circuit (60) is switched with theopening of the expansion valve (65) temporarily increased. And, when therefrigeration cycle operation of the refrigerant circuit (60) isswitched, the opening control means (72) reduces the once-increasedopening of the expansion valve (65).

As described above, when approaching the point just before theoccurrence of switching of the refrigeration cycle operation of therefrigerant circuit (60), the situation is that any increase in theamount of dehumidification and the amount of humidification is no longerexpected. To cope with this, in such a state, the opening control means(72) operates to increase the opening of the expansion valve (65), inthe first constructional example of the opening control means (72) inthe seventh invention. As the opening of the expansion valve (65)increases, the high-low pressure difference in the refrigerant cycle isreduced, and the input to the compressor (63) which compressesrefrigerants is reduced. Besides, when the opening of the expansionvalve (65) increases prior to switching of the operation of therefrigerant circuit (60), the capability to heat adsorbent and thecapability to cool adsorbent are lowered proportionally. This makes itpossible to reduce the time from when the refrigeration cycle operationof the refrigerant circuit (60) is switched to when the adsorbentreaches a temperature capable of allowing the adsorbent to effectsufficient moisture adsorption/desorption. As a result, the humiditycontrol capability of the humidity controller apparatus (10) isimproved.

A second constructional example of the opening control means (72) in theseventh invention is a means which performs, every time the operation ofthe refrigerant circuit (60) is switched, a control operation oftemporarily decreasing the opening of the expansion valve (65) below areference opening corresponding to the operational status of therefrigerant circuit (60) immediately after switching of the operation ofthe refrigerant circuit (60) and then increasing the opening of theexpansion valve (65) after an elapse of a predetermined length of timesince the switching of the operation of the refrigerant circuit (60).

In the second constructional example, the opening control means (72)performs a predefined control operation every time the refrigerationcycle operation of the refrigerant circuit (60) is switched. In thiscontrol operation, the opening control means (72) temporarily decreasesthe opening of the expansion valve (65) upon switching of therefrigeration cycle operation of the refrigerant circuit (60). At thattime, the opening control means (72) reduces the opening of theexpansion valve (65) to fall below a reference opening corresponding tothe operational status of the refrigerant circuit (60). Then, after anelapse of a predetermined length of time since the switching of therefrigeration cycle operation of the refrigerant circuit (60), theopening control means (72) expands the once-decreased opening of theexpansion valve (65).

To sum up, in the second constructional example of the opening controlmeans (72) in the seventh invention, the opening control means (72)temporarily reduces the opening of the expansion valve (65) at the stagejust after switching of the refrigeration cycle operation of therefrigerant circuit (60) where the adsorbents are required to be heatedand cooled rapidly. As the opening of the expansion valve (65)decreases, the high-low pressure difference in the refrigerant cycleincreases, and the temperature of refrigerant condensation rises whilethe temperature of refrigerant evaporation drops. Consequently, thetemperature of the adsorbent in the heat exchanger (61, 62) which hasconverted into a condenser is increased more rapidly, thereby making itpossible to secure the amount of humidification to an air stream and, onthe other hand, the temperature of the adsorbent in the heat exchanger(61, 62) which has converted into an evaporator is lowered more rapidly,thereby making it possible to secure the amount of dehumidification froman air stream.

EFFECTS

In the present invention, the humidity controller apparatus (10) isprovided with the interval set means (74). The switching time interval,at which the first operation and the second operation are interswitched,is set depending on the load of the humidity controller apparatus (10).Therefore, in accordance with the present invention, it is possible toadequately set the capability to control the humidity exerted by thehumidity controller apparatus (10) depending on the load of the humiditycontroller apparatus (10). In other words, it becomes possible to adjustthe humidity control capability of the humidity controller apparatus(10) without an excess or deficiency depending on the latent heat loadof a room. As a result, indoor comfort is improved to a further extentand, in addition, it is possible to aim at achieving energy savings byadequately adjusting the humidity control capability of the humiditycontroller apparatus.

In the second invention, the interval set means (74) reduces theswitching time interval with the increase in the load of the humiditycontroller apparatus (10), in consideration of the characteristic of thehumidity controller apparatus (10) which performs a so-called batchrunning operation, i.e., the characteristic that moistureadsorption/desorption for the adsorbent takes places intensively withina relatively short period of time after operational interswitching.Therefore, in accordance with the present invention, the humiditycontrol capability of the humidity controller apparatus (10) canassuredly be adjusted by a simple technique, such as by adjustment inthe switching interval time.

In the third invention, adsorption units are formed by the heatexchangers (61, 62) each supporting an adsorbent on its surface.Therefore, in the heat exchanger (61, 62) acting as an evaporator, heatof adsorption, generated when moisture is adsorbed on the adsorbentsupported on the surface of the evaporator heat exchanger (61, 62), isabsorbed by the refrigerant, thereby making it possible to increase theamount of moisture being adsorbed on the adsorbent. In addition, in theheat exchanger (61, 62) acting as a condenser, the adsorbent supportedon the surface of the condenser heat exchanger (61, 62) is heatedeffectively by the refrigerant, thereby making it possible to increasethe amount of moisture being desorbed from the adsorbent. Therefore, thepresent invention provides the humidity controller apparatus (10) whosehumidity control capability is high.

In the fourth invention, in an operational status in which a second airstream taken into the humidity controller apparatus (10) has a highertemperature than a first air stream, the adsorbent of the heat exchanger(61, 62) converting into an evaporator from a condenser is precooled bythe first air stream and the adsorbent of the heat exchanger (61, 62)converting into a condenser from an evaporator is preheated by thesecond air stream. In addition, in the fifth invention, in anoperational status in which a first air stream taken into the humiditycontroller apparatus (10) has a higher temperature than a second airstream, the adsorbent of the heat exchanger (61, 62) converting into anevaporator from a condenser is precooled by both the refrigerant and thesecond air stream and the adsorbent of the heat exchanger (61, 62)converting into a condenser from an evaporator is preheated by both therefrigerant and the first air stream.

Therefore, in accordance with the fourth and fifth inventions, it ispossible to reduce the time from when the refrigeration cycle operationof the refrigerant circuit (60) is switched to when the adsorbentreaches a temperature capable of allowing the adsorbent to effectsufficient moisture adsorption/desorption, and the amount of moisturebeing adsorbed by the adsorbent and the amount of moisture beingdesorbed from the adsorbent are increased. As a result, the humiditycontrol capability of the humidity controller apparatus (10) isimproved.

In the sixth invention, it is arranged that the capacity of thecompressor (63) is adjusted in response to switching of the operation ofthe refrigerant circuit (60). In addition, in the seventh invention, itis arranged that the opening of the expansion valve (65) is adjusted inresponse to switching of the operation of the refrigerant circuit (60).Therefore, in accordance with these inventions, it becomes possible tocontrol the capacity of the compressor (63) and the opening of theexpansion valve (65) with accuracy, thereby making it possible to aim ataccomplishing improvements in capability and efficiency of the humiditycontroller apparatus (10).

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a schematic cross sectional view of a humidity controllerapparatus of a first embodiment of the present invention, the view beingtaken along the line X-X in FIG. 1B;

FIG. 1B is a schematic top plan view of the humidity controllerapparatus of the first embodiment;

FIG. 1C is a schematic cross sectional view of the humidity controllerapparatus of the first embodiment, the view being taken along the lineY-Y in FIG. 1B;

FIG. 2A is a refrigerant circuit diagram showing an arrangement of arefrigerant circuit and a first refrigeration cycle of the refrigerantcircuit in the first embodiment;

FIG. 2B is a refrigerant circuit diagram showing an arrangement of therefrigerant circuit and a second refrigeration cycle of the refrigerantcircuit in the first embodiment;

FIG. 3 is a block diagram showing an arrangement of a controller of thehumidity controller apparatus in the first embodiment;

FIG. 4A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a first operation of a ventilationand dehumidification mode, the view being taken along the line X-X inFIG. 4B;

FIG. 4B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the first operation of theventilation and dehumidification mode;

FIG. 4C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the first operation of theventilation and dehumidification mode, the view being taken along theline Y-Y in FIG. 4B;

FIG. 5A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a second operation of the ventilationand dehumidification mode, the view being taken along the line X-X inFIG. 5B;

FIG. 5B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the second operation of theventilation and dehumidification mode;

FIG. 5C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the second operation of theventilation and dehumidification mode, the view being taken along theline Y-Y in FIG. 5B;

FIG. 6A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a first operation of a ventilationand humidification mode, the view being taken along the line X-X in FIG.6B;

FIG. 6B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the first operation of theventilation and humidification mode;

FIG. 6C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the first operation of theventilation and humidification mode, the view being taken along the lineY-Y in FIG. 6B;

FIG. 7A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a second operation of the ventilationand humidification mode, the view being taken along the line X-X of FIG.7B;

FIG. 7B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the second operation of theventilation and humidification mode;

FIG. 7C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the second operation of theventilation and humidification mode, the view being taken along the lineY-Y in FIG. 7B;

FIG. 8A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a first operation of a circulationand dehumidification mode, the view being taken along the line X-X inFIG. 8B;

FIG. 8B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the first operation of thecirculation and dehumidification mode;

FIG. 8C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the first operation of thecirculation and dehumidification mode, the view being taken along theline Y-Y in FIG. 8B;

FIG. 9A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a second operation of the circulationand dehumidification mode, the view being taken along the line X-X inFIG. 9B;

FIG. 9B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the second operation of thecirculation and dehumidification mode;

FIG. 9C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the second operation of thecirculation and dehumidification mode, the view being taken along theline Y-Y in FIG. 9B;

FIG. 10A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a first operation of a circulationand humidification mode, the view being taken along the line X-X in FIG.10B;

FIG. 10B is a schematic top plan view of the humidity controllerapparatus showing the flow of air streams in the first operation of thecirculation and humidification mode;

FIG. 10C is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in the first operation of thecirculation and humidification mode, the view being taken along the lineY-Y in FIG. 10B;

FIG. 11A is a cross sectional view of the humidity controller apparatusshowing the flow of air streams in a second operation of the circulationand humidification mode, the view being taken along the line X-X in FIG.11B;

FIG. 11B is a schematic top plan view of the humidity controllerapparatus showing the flows of air streams in the second operation ofthe circulation and humidification mode;

FIG. 11C is a cross sectional view of the humidity controller apparatusshowing the flows of air streams in the second operation of thecirculation and humidification mode, the view being taken along the lineY-Y in FIG. 11B;

FIG. 12 is an elapsed-time versus absolute-humidity relationship diagramgraphically showing variations in absolute humidity of first and secondair streams for the case where the switching time interval is threeminutes;

FIG. 13 is an elapsed-time versus absolute-humidity relationship diagramgraphically showing variations in absolute humidity of first and secondair streams for the case where the switching time interval is twominutes;

FIG. 14 is a time chart showing an operation state during a firstswitching control operation in a humidity controller apparatus of asecond embodiment of the present invention;

FIG. 15 is a time chart showing an operation state during a secondswitching control operation in the humidity controller apparatus of thesecond embodiment;

FIG. 16 is a time chart showing an operation state of a humiditycontroller apparatus in a third embodiment of the present invention;

FIG. 17 is a time chart showing an operation state of a humiditycontroller apparatus in a fourth embodiment of the present invention;

FIG. 18 is a time chart showing an operation state of a humiditycontroller apparatus in a fifth embodiment of the present invention; and

FIG. 19 is a time chart showing an operation state of a humiditycontroller apparatus in a sixth embodiment of the present invention.

BEST MODE FOR CARRYING OUT INVENTION

Hereinafter, embodiments of the present invention will be described indetail with reference to the drawings.

Embodiment 1 of Invention

As shown in FIGS. 1A, 1B, and 1C, a humidity controller apparatus (10)of a first embodiment of the present invention operates to dehumidifyand humidify air in an indoor space. The humidity controller apparatus(10) has a casing (11) shaped like a box. In FIG. 1B, the under side isa front side of the casing (11) and the upper side is a rear side of thecasing (11). In the following description, “right” and “left” mean,respectively, “right” and “left” relative to the figure referred to.

The casing (11) contains therein a refrigerant circuit (60) and othercomponents. The refrigerant circuit (60) is a closed circuit in which afirst heat exchanger (61), a second heat exchanger (62), a compressor(63), a four-way selector valve (64), and an electric expansion valve(65) are provided. The refrigerant circuit (60) is filled up with arefrigerant. In the refrigerant circuit (60), a vapor compressionrefrigeration cycle is carried out by circulation of the filledrefrigerant. The refrigerant circuit (60) will be described in detaillater.

The casing (11) has approximately a square shape when viewed from above,and is shaped like a flat box. An outside air suction opening (21) isformed in a left side plate (12) of the casing (11), such that it islocated adjacent to a rear plate (15) of the casing (11). Additionally,a room air suction opening (22) is formed in the left side plate (12),such that it is located adjacent to a front plate (14) of the casing(11). On the other hand, an exhaust air blowout opening (23) is formedin a right side plate (13) of the casing (11), such that it is locatedadjacent to the rear plate (15). Additionally, a supply air blowoutopening (24) is formed in the right side plate (13), such that it islocated adjacent to the front plate (14).

A first partition plate (31) is mounted within the casing (11), suchthat it stands nearer to the right side plate (13) than the centerrelative to the right-left direction. The first partition plate (31)divides an internal space (16) of the casing (11) into a left-hand sidespace and a right-hand side space. That is, a first space (17) isdefined on the left side of the first partition plate (31) while, on theother hand, a second space (18) is defined on the right side of thefirst partition plate (31).

A compressor (63) of the refrigerant circuit (60) is disposed in thesecond space (18) of the casing (11). In addition, although not shown inFIGS. 1A-1C, the electric expansion valve (65) and the four-way selectorvalve (64) of the refrigerant circuit (60) are also disposed in thesecond space (18). Furthermore, an exhaust fan (26) and a supply fan(25) are accommodated in the second space (18). The exhaust fan (26) isconnected to the exhaust air blowout opening (23). The supply fan (25)is connected to the supply air blowout opening (24).

A second partition plate (32), a third partition plate (33), and a sixthpartition plate (36) are mounted in the first space (17) of the casing(11). The second partition plate (32) is mounted, such that it standsadjacent to the front plate (14). The third partition plate (33) ismounted, such that it stands adjacent to the rear plate (15). And, thefirst space (17) is divided by the second and third partition plates(32, 33) into three spaces in the direction from the front to the rearside. The sixth partition plate (36) is mounted in a space definedbetween the second partition plate (32) and the third partition plate(33). The sixth partition plate (36) is mounted, such that it standscentrally relative to the right-left width direction of the first space(17).

A space defined between the second partition plate (32) and the thirdpartition plate (33) is divided by the sixth partition plate (36) into aright-hand space and a left-hand space. Of these spaces, the right-handside space constitutes a first heat exchange chamber (41) in which isdisposed the first heat exchanger (61). On the other hand, the left-handside space constitutes a second heat exchange chamber (42) in which isdisposed the second heat exchanger (62).

The heat exchangers (61, 62) are each shaped like a thick flat plate asa whole. And, the first heat exchanger (61) is disposed, such that ithorizontally crosses the first heat exchange chamber (41). On the otherhand, the second heat exchanger (62) is disposed, such that ithorizontally crosses the second heat exchange chamber (42). The firstand second heat exchangers (61, 62) will later be described in detail.

A fifth partition plate (35) is mounted in a space of the first space(17) sandwiched between the third partition plate (33) and the rearplate (15) of the casing (11). The fifth partition plate (35) isdisposed, such that it crosses a heightwise middle region of the space.The fifth partition plate (35) vertically divides the space (see FIG.1A). More specifically, a space defined on the upper side of the fifthpartition plate (35) constitutes a first inflow path (43) while, on theother hand, a space defined on the lower side of the fifth partitionplate (35) constitutes a first outflow path (44). The first inflow path(43) is in communication with the outside air suction opening (21). Thefirst outflow path (44) is in communication with the exhaust air blowoutopening (23) via the exhaust fan (26).

On the other hand, a fourth partition plate (34) is mounted in a spaceof the first space (17) defined between the second partition plate (32)and the front plate (14) of the casing (11). The fourth partition plate(34) is disposed, such that it crosses a heightwise middle region of thespace. The fourth partition plate (34) vertically divides the space (seeFIG. 1C). More specifically, a space defined on the upper side of thefourth partition plate (34) constitutes a second inflow path (45) while,on the other hand, a space defined on the lower side of the fourthpartition plate (34) constitutes a second outflow path (46). The secondinflow path (45) is in communication with the room air suction opening(22). The second outflow path (46) is in communication with the supplyair blowout opening (24) via the supply fan (25).

Four openings (51, 52, 53, 54) are formed in the third partition plate(33) (see FIG. 1A). The first opening (51), located upper right of thethird partition plate (33), establishes communication between the upperside of the first heat exchanger (61) in the first heat exchange chamber(41) and the first inflow path (43). The second opening (52), locatedupper left of the third partition plate (33), establishes communicationbetween the upper side of the second heat exchanger (62) in the secondheat exchange chamber (42) and the first inflow path (43). The thirdopening (53), located lower right of the third partition plate (33),establishes communication between the lower side of the first heatexchanger (61) in the first heat exchange chamber (41) and the firstoutflow path (44). The fourth opening (54), located lower left of thethird partition plate (33), establishes communication between the lowerside of the second heat exchanger (62) in the second heat exchangechamber (42) and the first outflow path (44).

Four openings (55, 56, 57, 58) are formed in the second partition plate(32) (see FIG. 1C). The fifth opening (55), located upper right of thesecond partition plate (32), establishes communication between the upperside of the first heat exchanger (61) in the first heat exchange chamber(41) and the second inflow path (45). The sixth opening (56), locatedupper left of the second partition plate (32), establishes communicationbetween the upper side of the second heat exchanger (62) in the secondheat exchange chamber (42) and the second inflow path (45). The seventhopening (57), located lower right of the second partition plate (32),establishes communication between the lower side of the first heatexchanger (61) in the first heat exchange chamber (41) and the secondoutflow path (46). The eighth opening (58), located lower left of thesecond partition plate (32), establishes communication between the lowerside of the second heat exchanger (62) in the second heat exchangechamber (42) and the second outflow path (46).

Each opening (51, 52, 53, 54) of the third partition plate (33) isprovided with a respective openable/closable damper. Likewise, eachopening (55, 56, 57, 58) of the second partition plate (32) is providedwith a respective openable/closable damper. Each opening (51, . . . ,55, . . . ) is selectively placed in the open state or in the closedstate by opening or closing its associated damper. And, the damperprovided at each opening (51, . . . , 55, . . . ) constitutes aswitching mechanism (50) for switching of the distribution routes offirst and second air streams in the casing (11).

With reference to FIG. 2A and FIG. 2B, the refrigerant circuit (60) isdescribed below.

The discharge side of the compressor (63) is connected to a first portof the four-way selector valve (64). The suction side of the compressor(63) is connected to a second port of the four-way selector valve (64).One end of the first heat exchanger (61) is connected to a third port ofthe four-way selector valve (64). The other end of the first heatexchanger (61) is connected, through the electric expansion valve (65),to one end of the second heat exchanger (62). The other end of thesecond heat exchanger (62) is connected to a fourth port of the four-wayselector valve (64).

The compressor (63) is a so-called hermetic compressor. Electric poweris supplied, through an inverter, to an electric motor (not shown) ofthe compressor (63).

When the output frequency of the inverter is varied, the rotating speedof the electric motor likewise is varied. With such variation, thedisplacement volume of the compressor (63) varies. Stated another way,the compressor (63) is configured to be variable in capacity.

Each of the first and second heat exchangers (61, 62) is formed by a finand tube heat exchanger of the so-called cross fin type having heattransfer pipes and a large number of fins. In addition, an adsorbentsuch as zeolite is supported approximately all over the external surfaceof each of the first and second heat exchangers (61, 62). And, the firstheat exchanger (61) constitutes a first adsorption unit while, on theother hand, the second heat exchanger (62) constitutes a secondadsorption unit.

The four-way selector valve (64) is configured, such that it selectablychanges state to a first state that allows communication between thefirst port and the third port and communication between the second portand the fourth port (as indicated in FIG. 2A) or to a second state thatallows communication between the first port and the fourth port andcommunication between the second port and the third port (as indicatedin FIG. 2B). And, the refrigerant circuit (60) is configured, such thatit selectively performs, by switching of the four-way selector valve(64), a first refrigeration cycle operation in which the first heatexchanger (61) functions as a condenser while, on the other hand, thesecond heat exchanger (62) functions as an evaporator or a secondrefrigeration cycle operation in which the first heat exchanger (61)functions as an evaporator while, on the other hand, the second heatexchanger (62) functions as a condenser.

The humidity controller apparatus (10) is equipped with a controller(70). As shown in FIG. 3, the controller (70) includes a capacitycontrol part (71), an opening control part (72), a switching controlpart (73), and an interval set part (74).

The capacity control part (71) is configured to control the capacity ofthe compressor (63). More specifically, the capacity control part (71)adjusts the capacity of the compressor (63) by adjusting the outputfrequency of the inverter. The capacity control part (71) adjusts thecapacity of the compressor (63) depending on the operational status ofthe humidity controller apparatus (10).

The opening control part (72) is configured, such that it conductscontrol of the opening of the electric expansion valve (65). The openingcontrol part (72) adjusts the opening of the electric expansion valve(65) depending on the operational status of the refrigerant circuit(60).

The switching control part (73) is configured, such that it conductsswitching of the operation of the refrigerant circuit (60)simultaneously with switching of the distribution routes of the firstand second air streams. More specifically, the switching control part(73) conducts the operation of the four-way selector valve (64) and theoperation of the damper of each opening (51, . . . , 55, . . . ) whichconstitutes a respective switching mechanism (50). In addition, theswitching control part (73) periodically controls the operation of thefour-way selector valve (64) and the operation of the switchingmechanism (50) at a predetermined switching time interval.

The interval set part (74) is configured, such that it sets theswitching time interval. In other words, the time interval, at which theswitching control part (73) operates the four-way selector valve (64)and the switching mechanism (50), is set by the interval set part (74).In addition, the interval set part (74) constitutes an interval setmeans which sets a switching time interval depending on the load of thehumidity controller apparatus (10).

Humidity Control Operation of Humidity Controller Apparatus

The humidity control operation of the humidity controller operation (10)is described. The operation of the humidity controller operation (10) isswitchable between a ventilation/dehumidification mode, aventilation/humidification mode, a circulation/dehumidification mode,and a circulation/humidification mode. In addition, in the humiditycontroller apparatus (10), a first operation and a second operation arealternately repeatedly performed at a predetermined time interval duringeach mode.

Ventilation/Dehumidification Mode

In the ventilation/dehumidification mode, the supply fan (25) and theexhaust fan (26) are operated in the humidity controller apparatus (10).And, the humidity controller apparatus (10) takes in outside air (OA) asa first air stream and supplies it into a room while taking in room air(RA) as a second air stream and discharging it to outside the room.

In the first place, a first operation of theventilation/dehumidification mode is described with reference to FIGS.2A and 2B and FIGS. 4A-4C. In the first operation, adsorbentregeneration takes place in the first heat exchanger (61) while, on theother hand, dehumidification of outside air (OA) as a first air streamtakes place in the second heat exchanger (62).

In the first operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2A. Inthis state, when the compressor (63) is operated, the refrigerantcirculates in the refrigerant circuit (60), and a first refrigerationcycle operation is carried out in which the first heat exchanger (61)and the second heat exchanger (62) act as a condenser and as anevaporator, respectively.

More specifically, the refrigerant discharged out of the compressor (63)gives off the heat and condenses in the first heat exchanger (61).Thereafter, the refrigerant is delivered to the electric expansion valve(65) and is reduced in pressure. The pressure-reduced refrigerantabsorbs heat and evaporates in the second heat exchanger (62).Thereafter, the refrigerant is drawn into the compressor (63) and iscompressed. Then, the compressed refrigerant is again discharged out ofthe compressor (63).

In addition, in the first operation, the damper of each opening (51, . .. , 55, . . . ) which constitutes a respective switching mechanism (50)is set in a first distribution state of the ventilation/dehumidificationmode. In this state, the second opening (52), the third opening (53),the fifth opening (55), and the eighth opening (58) enter the open statewhile, on the other hand, the first opening (51), the fourth opening(54), the sixth opening (56), and the seventh opening (57) enter theclosed state. Consequently, as shown in FIGS. 4A-4C, room air (RA) as asecond air stream is supplied to the first heat exchanger (61) while, onthe other hand, outside air (OA) as a first air stream is supplied tothe second heat exchanger (62).

More specifically, the second air stream entered from the room airsuction opening (22) is delivered, through the second inflow path (45)and then through the fifth opening (55), to the first heat exchangechamber (41). In the first heat exchange chamber (41), the second airstream passes from up to down through the first heat exchanger (61). Inthe first heat exchanger (61), the adsorbent supported on the externalsurface is heated by the refrigerant, and moisture desorption from theadsorbent takes place. The desorbed moisture from the adsorbent is givento the second air stream passing through the first heat exchanger (61).The second air stream moisturized in the first heat exchanger (61) flowsout, through the first heat exchange chamber (41) and then through thethird opening (53), to the first outflow path (44). Thereafter, thesecond air stream is drawn into the exhaust fan (26) and is dischargedto outside the room from the exhaust air blowout opening (23) as exhaustair (EA).

Meanwhile, the first air stream entered from the outside air suctionopening (21) is delivered, through the first inflow path (43) and thenthrough the second opening (52), to the second heat exchange chamber(42). In the second heat exchange chamber (42), the first air streampasses from up to down through the second heat exchanger (62). In thesecond heat exchanger (62), moisture present in the first air stream isadsorbed on the adsorbent supported on the surface of the second heatexchanger (62), and resulting heat of adsorption is absorbed by therefrigerant. The first air stream dehumidified in the second heatexchanger (62) flows out, through the second heat exchange chamber (42)and then through the eighth opening (58), to the second outflow path(46). Thereafter, the first air stream is drawn into the supply fan (25)and is supplied into the room from the supply air blowout opening (24)as supply air (SA).

Next, a second operation of the ventilation/dehumidification mode isdescribed with reference to FIGS. 2A and 2B and FIGS. 5A-5C. In thesecond operation, adsorbent regeneration takes place in the second heatexchanger (62) while, on the other hand, dehumidification of outside air(OA) as a first air stream takes place in the first heat exchanger (61).

In the second operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2B. Inthis state, when the compressor (63) is operated, the refrigerantcirculates in the refrigerant circuit (60), and a second refrigerationcycle operation is carried out in which the first heat exchanger (61)and the second heat exchanger (62) act as an evaporator and as acondenser, respectively.

More specifically, the refrigerant discharged out of the compressor (63)gives off the heat and condenses in the second heat exchanger (62).Thereafter, the refrigerant is delivered to the electric expansion valve(65) and is reduced in pressure. The pressure-reduced refrigerantabsorbs heat and evaporates in the first heat exchanger (61).Thereafter, the refrigerant is drawn into the compressor (63) and iscompressed. Then, the compressed refrigerant is again discharged out ofthe compressor (63).

In addition, in the second operation, the damper of each opening (51, .. . , 55, . . . ) which constitutes a respective switching mechanism(50) is set in a second distribution state of theventilation/dehumidification mode. In this state, the first opening(51), the fourth opening (54), the sixth opening (56), and the seventhopening (57) enter the open state while, on the other hand, the secondopening (52), the third opening (53), the fifth opening (55), and theeighth opening (58) enter the closed state. Consequently, as shown inFIGS. 5A-5C, outside air (OA) as a first air stream is supplied to thefirst heat exchanger (61) while, on the other hand, room air (RA) as asecond air stream is supplied to the second heat exchanger (62).

More specifically, the second air stream entered from the room airsuction opening (22) is delivered, through the second inflow path (45)and then through the sixth opening (56), to the second heat exchangechamber (42). In the second heat exchange chamber (42), the second airpasses from up to down through the second heat exchanger (62). In thesecond heat exchanger (62), the adsorbent supported on the externalsurface is heated by the refrigerant, and moisture desorption from theadsorbent takes place. The moisture desorbed from the adsorbent is givento the second air stream passing through the second heat exchanger (62).The second air stream moisturized in the second heat exchanger (62)flows out, through the second heat exchange chamber (42) and thenthrough the fourth opening (54), to the first outflow path (44).Thereafter, the second air stream is drawn into the exhaust fan (26) andis discharged to outside the room from the exhaust air blowout opening(23) as exhaust air (EA).

Meanwhile, the first air stream entered from the outside air suctionopening (21) is delivered, through the first inflow path (43) and thenthrough the first opening (51), to the first heat exchange chamber (41).In the first heat exchange chamber (41), the first air stream passesfrom up to down through the first heat exchanger (61). In the first heatexchanger (61), moisture present in the first air stream is adsorbed bythe adsorbent supported on the surface of the first heat exchanger (61),and resulting heat of adsorption is absorbed by the refrigerant. Thefirst air-stream dehumidified in the first heat exchanger (61) flowsout, through the first heat exchange chamber (41) and then through theseventh opening (57), to the second outflow path (46). Thereafter, thefirst air stream is drawn into the supply fan (25) and is supplied intothe room from the supply air blowout opening (24) as supply air (SA).

Ventilation/Humidification Mode

In the ventilation/humidification mode, the supply fan (25) and theexhaust fan (26) are operated in the humidity controller apparatus (10).And, the humidity controller apparatus (10) takes in room air (RA) as afirst air stream and discharges it to outside the room while, on theother hand, taking in outside air (OA) as a second air stream andsupplying it into the room.

In the first place, a first operation in the ventilation/humidificationmode is described with reference to FIGS. 2A and 2B and FIGS. 6A-6C. Inthe first operation, humidification of outside air (OA) as a second airstream takes place in the first heat exchanger (61) while, on the otherhand, recovery of moisture from room air (RA) as a first air streamtakes place in the second heat exchanger (62).

In the first operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2A. Inthis state, when the compressor (63) is operated, the refrigerantcirculates in the refrigerant circuit (60), and a first refrigerationcycle operation is carried out in which the first heat exchanger (61)and the second heat exchanger (62) act as a condenser and as anevaporator, respectively.

In addition, in the first operation, the damper of each opening (51, . .. , 55, . . . ) which constitutes a respective switching mechanism (50)is set in a first distribution state of the ventilation/humidificationmode. In this state, the first opening (51), the fourth opening (54),the sixth opening (56), and the seventh opening (57) enter the openstate while, on the other hand, the second opening (52), the thirdopening (53), the fifth opening (55), and the eighth opening (58) enterthe closed state. Consequently, as shown in FIGS. 6A-6C, outside air(OA) as a second air stream is supplied to the first heat exchanger (61)while, on the other hand, room air (RA) as a first air stream issupplied to the second heat exchanger (62).

More specifically, the first air stream entered from the room airsuction opening (22) is delivered, through the second inflow path (45)and then through the sixth opening (56), to the second heat exchangechamber (42). In the second heat exchange chamber (42), the first airstream passes from up to down through the second heat exchanger (62). Inthe second heat exchanger (62), moisture present in the first air streamis adsorbed on the adsorbent supported on the surface of the second heatexchanger (62), and resulting heat of adsorption is absorbed by therefrigerant. Thereafter, the moisture-removed first air stream passesthrough the fourth opening (54), the first outflow path (44), and theexhaust fan (26) in that order, and is discharged to outside the roomfrom the exhaust air blowout opening (23) as exhaust air (EA).

Meanwhile, the second air stream entered from the outside air suctionopening (21) is delivered, through the first inflow path (43) and thenthrough the first opening (51), to the first heat exchange chamber (41).In the first heat exchange chamber (41), the second air stream passesfrom up to down through the first heat exchanger (61). In the first heatexchanger (61), the adsorbent supported on the external surface isheated by the refrigerant, and moisture desorption from the adsorbenttakes place. The moisture desorbed from the adsorbent is given to thesecond air stream passing through the first heat exchanger (61).Thereafter, the second air stream thus humidified passes through theseventh opening (57), the second outflow path (46), and the supply fan(25) in that order, and is supplied into the room from the supply airblowout opening (24) as supply air (SA).

Next, a second operation of the ventilation/humidification mode isdescribed with reference to FIGS. 2A and 2B and FIGS. 7A-7C. In thesecond operation, humidification of outside air (OA) as a second airstream takes place in the second heat exchanger (62) while, on the otherhand, recovery of moisture from room air (RA) as a first air streamtakes place in the first heat exchanger (61).

In the second operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2B. Inthis state, when the compressor (63) is operated, the refrigerantcirculates in the refrigerant circuit (60), and a second refrigerationcycle operation is carried out in which the first heat exchanger (61)and the second heat exchanger (62) act, respectively, as an evaporatorand as a condenser.

In addition, in the second operation, the damper of each opening (51, .. . , 55, . . . ) which constitutes a respective switching mechanism(50) is set in a second distribution state of theventilation/humidification mode. In this state, the second opening (52),the third opening (53), the fifth opening (55), and the eighth opening(58) enter the open state while, on the other hand, the first opening(51), the fourth opening (54), the sixth opening (56), and the seventhopening (57) enter the closed state. Consequently, as shown in FIGS.7A-7C, room air (RA) as a first air stream is supplied to the first heatexchanger (61) while, on the other hand, outside air (OA) as a secondair stream is supplied to the second heat exchanger (62).

More specifically, the first air stream entered from the room airsuction opening (22) is delivered, through the second inflow path (45)and then through the fifth opening (55), to the first heat exchangechamber (41). In the first heat exchange chamber (41), the first airstream passes from up to down through the first heat exchanger (61). Inthe first heat exchanger (61), moisture present in the first air streamis adsorbed on the adsorbent supported on the surface of the first heatexchanger (61), and resulting heat of adsorption is absorbed by therefrigerant. Thereafter, the moisture-removed first air stream passesthrough the third opening (53), the first outflow path (44), and theexhaust fan (26) in that order, and is discharged from the exhaust airblowout opening (23) to outside the room as exhaust air (EA).

Meanwhile, the second air stream entered from the outside air suctionopening (21) is delivered, through the first inflow path (43) and thenthrough the second opening (52), to the second heat exchange chamber(42). In the second heat exchange chamber (42), the second air streampasses from up to down through the second heat exchanger (62). In thesecond heat exchanger (62), the adsorbent supported on the externalsurface is heated by the refrigerant and, as a result, moisturedesorption from the adsorbent takes place. The moisture desorbed fromthe adsorbent is given to the second air stream passing through thesecond heat exchanger (62). Thereafter, the second air stream thushumidified passes through the eighth opening (58), the second outflowpath (46), and the supply fan (25) in that order, and is supplied, assupply air (SA), from the supply air blowout opening (24) into the room.

Circulation/Dehumidification Mode

In the circulation/dehumidification mode, the supply fan (25) and theexhaust fan (26) are operated in the humidity controller apparatus (10).And, the humidity controller apparatus (10) takes in room air (RA) as afirst air stream and then sends it back into the room afterdehumidification while, on the other hand, the humidity controllerapparatus (10) takes in outside air (OA) as a second air stream and thendischarges it outside the room, together with moisture desorbed from theadsorbent.

In the first place, a first operation of thecirculation/dehumidification mode is described with reference to FIGS.2A and 2B and FIGS. 8A-8C. In the first operation, adsorbentregeneration takes place in the first heat exchanger (61) while, on theother hand, dehumidification of room air (RA) as a first air streamtakes place in the second heat exchanger (62).

In the first operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2A, and afirst refrigeration cycle operation is carried out. In addition, thedamper of each opening (51, . . . , 55, . . . ) which constitutes arespective switching mechanism (50) is set in a first distribution stateof the circulation/dehumidification mode. In this state, the firstopening (51), the third opening (53), the sixth opening (56), and theeighth opening (58) enter the open state while, on the other hand, thesecond opening (52), the fourth opening (54), the fifth opening (55),and the seventh opening (57) enter the closed state. Consequently, asshown in FIGS. 8A-8C, outside air (OA) as a second air stream issupplied to the first heat exchanger (61) while, on the other hand, roomair (RA) as a first air stream is supplied to the second heat exchanger(62).

More specifically, after flowing in from the outside air suction opening(21), the second air stream is introduced into the first heat exchangechamber (41) and passes through the first heat exchanger (61). In thefirst heat exchanger (61), the adsorbent supported on the externalsurface is heated by the refrigerant, as a result of which the adsorbentis regenerated. And, the second air stream which was given moisturedesorbed from the adsorbent is discharged to outside the room from theexhaust air blowout opening (23) as exhaust air (EA).

Meanwhile, after flowing in from the room air suction opening (22), thefirst air stream is introduced into the second heat exchange chamber(42) and passes through the second heat exchanger (62). In the secondheat exchanger (62), moisture present in the first air stream isadsorbed on the adsorbent supported on the surface of the second heatexchanger (62). Resulting heat of adsorption is absorbed by therefrigerant. And, the first air stream dehumidified in the second heatexchanger (61) is supplied into the room from the supply air blowoutopening (24) as supply air (SA).

Next, a second operation of the circulation/dehumidification mode isdescribed with reference to FIGS. 2A and 2B and FIGS. 9A-9C. In thesecond operation, regeneration of adsorbent takes place in the secondheat exchanger (62) while, on the other hand, dehumidification of roomair (RA) as a first air stream takes place in the first heat exchanger(61).

In the second operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2B, and asecond refrigeration cycle operation is carried out. In addition, thedamper of each opening (51, . . . , 55, . . . ) which constitutes arespective switching mechanism (50) is set in a second distributionstate of the circulation/dehumidification mode. In this state, thesecond opening (52), the fourth opening (54), the fifth opening (55),and the seventh opening (57) enter the open state. On the other hand,the first opening (51), the third opening (53), the sixth opening (56),and the eighth opening (58) enter the closed state. Consequently, asshown in FIGS. 9A-9C, room air (RA) as a first air stream is supplied tothe first heat exchanger (61) while, on the other hand, outside air (OA)as a second air stream is supplied to the second heat exchanger (62).

More specifically, after flowing in from the outside air suction opening(21), the second air stream is introduced into the second heat exchangechamber (42) and passes through the second heat exchange chamber (62).In the second heat exchanger (62), the adsorbent supported on theexternal surface is heated by the refrigerant, as a result of which theadsorbent is regenerated. And, the second air stream which was givenmoisture desorbed from the adsorbent is discharged to outside the roomfrom the exhaust air blowout opening (23) as exhaust air (EA).

Meanwhile, after flowing in from the room air suction opening (22), thefirst air stream is introduced into the first heat exchange chamber (41)and passes through the first heat exchanger (61). In the first heatexchanger (61), moisture present in the first air stream is adsorbed onthe adsorbent supported on the external surface of the first heatexchanger (61). Resulting heat of adsorption is absorbed by therefrigerant. And, the first air stream dehumidified in the first heatexchanger (61) is supplied into the room from the supply air blowoutopening (24) as supply air (SA).

Circulation/Humidification Mode

In the circulation/humidification mode, the supply fan (25) and theexhaust fan (26) are operated in the humidity controller apparatus (10).And, the humidity controller apparatus (10) takes in outdoor air (OA) asa first air stream and then discharges it to outside the room aftermoisture removal while, on the other hand, the humidity controllerapparatus (10) takes in room air (RA) as a second air stream and thensends it back into the room after dehumidification.

In the first place, a first operation of the circulation/humidificationmode is described with reference to FIGS. 2A and 2B and FIGS. 10A-10C.In the first operation, humidification of room air (RA) as a second airstream takes place in the first heat exchanger (61) and recovery ofmoisture from outside air (OA) as a first air stream takes place in thesecond heat exchanger (62).

In the first operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2A, and afirst refrigeration cycle operation is carried out. In addition, thedamper of each opening (51, . . . , 55, . . . ) which constitutes arespective switching mechanism (50) is set in a first distribution stateof the circulation/humidification mode. In this state, the secondopening (52), the fourth opening (52), the fifth opening (55), and theseventh opening (57) enter the open state. On the other hand, the firstopening (51), the third opening (53), the sixth opening (56), and theeighth opening (58) enter the closed state. Consequently, as shown inFIGS. 10A-10C, room air (RA) as a second air stream is supplied to thefirst heat exchanger (61) while, on the other hand, outside air (OA) asa first air stream is supplied to the second heat exchanger (62).

More specifically, after flowing in from the outside air suction opening(21), the first air stream is introduced into the second heat exchangechamber (42) and passes through the second heat exchanger (62). In thesecond heat exchanger (62), moisture present in the first air stream isadsorbed on the adsorbent supported on the surface of the second heatexchanger (62), and resulting heat of adsorption is absorbed by therefrigerant. And, the moisture-removed first air stream is discharged tooutside the room from the exhaust air blowout opening (23) as exhaustair (EA).

Meanwhile, after flowing in from the room air suction opening (22), thesecond air stream is introduced into the first heat exchange chamber(41) and passes through the first heat exchanger (61). In the first heatexchanger (61), the adsorbent supported on the external surface isheated by the refrigerant, as a result of which the adsorbent isregenerated. And, the second air stream humidified by moisture desorbedfrom the adsorbent is supplied into the room from the supply air blowoutopening (24) as supply air (SA).

Next, a second operation of the circulation/humidification mode isdescribed with reference to FIGS. 2A and 2B and FIGS. 11A-11C. In thesecond operation, humidification of room air (RA) as a second air streamtakes place in the second heat exchanger (62) and recovery of moisturefrom outside air (OA) as a first air stream takes place in the firstheat exchanger (61).

In the second operation, in the refrigerant circuit (60) the four-wayselector valve (64) changes state to a state as shown in FIG. 2B, and asecond refrigeration cycle operation is carried out. In addition, thedamper of each opening (51, . . . , 55, . . . ) which constitutes arespective switching mechanism (50) is set in a second distributionstate of the circulation/humidification mode. In this state, the firstopening (51), the third opening (53), the sixth opening (56), and theeighth opening (58) enter the open state. On the other hand, the secondopening (52), the fourth opening (54), the fifth opening (55), and theseventh opening (57) enter the closed state. Consequently, as shown inFIGS. 11A-11C, outside air (OA) as a first air stream is supplied to thefirst heat exchanger (61) while, on the other hand, room air (RA) as asecond air stream is supplied to the second heat exchanger (62).

More specifically, after flowing in from the outside air suction opening(21), the first air stream is introduced into the first heat exchangechamber (41) and passes through the first heat exchanger (61). In thefirst heat exchanger (61), moisture present in the first air stream isadsorbed on the adsorbent supported on the surface of the first heatexchanger (61), and resulting heat of adsorption is absorbed by therefrigerant. And, the moisture-removed first air stream is discharged tooutside the room from the exhaust air blowout opening (23) as exhaustair (EA).

Meanwhile, after flowing in from the room air suction opening (22), thesecond air stream flows into the second heat exchange chamber (42) andpasses through the second heat exchanger (62). In the second heatexchanger (62), the adsorbent supported on the external surface isheated by the refrigerant, as a result of which the adsorbent isregenerated. And, the second air stream humidified by moisture desorbedfrom the adsorbent is supplied into the room from the supply air blowoutopening (24) as supply air (SA).

Control Operation of Controller

The control operation of the controller (70) is described.

The capacity control part (71) of the controller (70) maintains thecapacity of the compressor (63) at a reference capacity. In other words,the capacity control part (71) keeps the capacity of the compressor (63)at a constant capacity, regardless of the state of the switchingmechanism (50) and the operational switching of the refrigerant circuit(60). The reference capacity of the compressor (63) is a capacity whichis set depending on the load of the humidity controller apparatus (10)(i.e., the amount of dehumidification or the amount of humidificationrequired to the humidity controller apparatus (10) depending on theindoor latent heat load).

The opening control part (72) of the controller (70) maintains theopening of the electric expansion valve (65) at a reference opening. Inother words, the opening control part (72) keeps the opening of theelectric expansion valve (65) at a constant opening, regardless of thestate of the switching mechanism (50) and the operational switching ofthe refrigerant circuit (60). The reference opening of the electricexpansion valve (65) is an opening which is set depending on theoperational status of the refrigerant circuit (60) (e.g., thetemperature of air delivered to the heat exchangers (61, 62) as a firstor second air stream and the temperature and the pressure of refrigerantat each part of the refrigerant circuit (60)).

The switching control part (73) of the controller (70) operates thefour-way selector valve (64) and the switching mechanism (50) at aswitching time interval set by the interval set part (74) so that theoperation of the refrigerant circuit (60) is switched simultaneouslywith switching of the distribution routes of first and second airstreams.

The interval set part (74) of the controller (70) sets a switching timeinterval depending on the load of the humidity controller apparatus(10). More specifically, the interval set part (74) makes a comparisonbetween an actual measurement value and a target value of the relativehumidity of room air and then adjusts the switching time interval sothat the actual measurement value and the target value agree with eachother. In doing so, the interval set part (74) sets the switching timeinterval shorter as the load of the humidity controller apparatus (10)increases, i.e., as the difference between an actual measurement valueand a target value of the relative humidity of room air increases.

Suppose here that an interval of three minutes is set as a referencevalue of the switching time interval. It should be noted that any of thefollowing switching time interval numeric values is merely an example.When there is produced a great difference between an actual measurementvalue and a target value of the room air relative humidity (for example,immediately after activating the humidity controller apparatus (10)),the interval set part (74) reduces the switching time interval to aninterval of two minutes from an interval of three minutes, therebyincreasing the humidity control capability of the humidity controllerapparatus (10). Thereafter, when the actual measurement value of theroom air relative humidity approaches the target value, the interval setpart (74) brings the switching time interval back to an interval ofthree minutes from an interval of two minutes.

In addition, if the actual measurement value of the indoor relativehumidity exceeds the target value during humidification, or if theactual measurement value of the indoor relative humidity falls below thetarget value during dehumidification, then the interval set part (74)extends the switching time interval from an interval of three minutes toan interval of four minutes, thereby reducing the humidity controlcapability of the humidity controller apparatus (10).

With reference to FIGS. 12 and 13, the reason that the humidity controlcapability of the humidity controller apparatus (10) varies with thechange in switching time interval is described. FIGS. 12 and 13graphically show variations with time in absolute humidity of each offirst and second air streams after passage through the second heatexchanger (62) during the ventilation/dehumidification mode. Inaddition, in FIGS. 12 and 13, the point of time when the first operationof the humidity controller apparatus (10) is started serves as astarting point, i.e., a zero-minute elapsed time point.

When the switching time interval is set at an interval of three minutes(see FIG. 12), the absolute humidity of the first air stream afterpassage through the second heat exchanger (62) drops abruptly withinabout 20 seconds from the start of the first operation. Thereafter, theabsolute humidity of the first air stream increases to the point of timeat which about two minutes have elapsed since the start of the firstoperation. Then, the absolute humidity of the first air stream remainsat relatively high levels until switching to the second operation. Afterthe switching to the second operation, the absolute humidity of thesecond air stream after passage through the second heat exchanger (62)rises abruptly within about 25 seconds from the start of the secondoperation. Thereafter, the absolute humidity of the second air streamdrops to the point of time at which about two minutes have elapsed sincethe start of the second operation. During a period from that time to thepoint of time of switching to the second operation, the second airstream is little humidified.

As can be seen from the above, most of moisture adsorption on theadsorbent taking place in a single first operation is effectedintensively within a short period of time from the start of the firstoperation. On the other hand, most of moisture desorption from theadsorbent taking place in a single second operation is effectedintensively within a short period of time from the start of the secondoperation. The process of such adsorption/desorption is the same as inthe case where the switching time interval is set at an interval of twominutes (see FIG. 13). For example, within a period of two minutes fromthe start of a first operation, the integration value of amounts ofdehumidification from a first air stream for the case where theswitching time interval is set at an interval of two minutes isapproximately the same as that for the case where the switching timeinterval is set at an interval of three minutes. In addition, forexample, within a period of two minutes from the start of a secondoperation, the integration value of amounts of humidification to asecond air stream for the case where the switching time interval is setat an interval of two minutes is approximately the same as that for thecase where the switching time interval is set at an interval of threeminutes. Accordingly, if the frequency of a first operation and thefrequency of a second operations are increased by reducing the switchingtime interval, this increases the amount of dehumidification from afirst air stream and the amount of humidification to a second airstream.

Effects of Embodiment 1

In the present embodiment, the controller (70) is provided with theinterval set part (74). The switching time interval, at which the firstoperation and the second operation are interswitched, is set dependingon the load of the humidity controller apparatus (10). As a result ofsuch arrangement in the present embodiment, the humidity controlcapability exerted by the humidity controller apparatus (10) is setadequately depending on the load of the humidity controller apparatus(10). Stated another way, it becomes possible to adequately set thehumidity control capability of the humidity controller apparatus (10)depending on the indoor latent heat load without an excess ordeficiency. As the result of this, indoor comfort is improved to afurther extent and, in addition, energy savings are achieved byadequately adjusting the humidity control capability of the humiditycontroller apparatus.

In addition, the interval set means (74) of the present embodimentreduces the switching time interval with the increase in the load of thehumidity controller apparatus (10), in consideration of thecharacteristic of the humidity controller apparatus (10) which performsa so-called batch running operation, i.e., the characteristic thatmoisture adsorption/desorption for the adsorbent takes placesintensively within a relatively short period of time after operationalinterswitching. Therefore, in accordance with the present embodiment,the humidity control capability of the humidity controller apparatus(10) can assuredly be adjusted by a simple technique, such as byadjustment in the switching interval time.

Modified Version of Embodiment 1

In the above-described embodiment, the humidity control function of thehumidity controller apparatus (10) may be on/off controlled depending onthe humidity control load, in addition to adjustment in the switchingtime interval by the interval set part (74) of the controller (70). Forexample, if the humidity control capability of the humidity controllerapparatus (10) is excessive relative to the indoor latent heat load evenwhen the switching time interval is set at an upper limit, it may bearranged that the compressor (63) is stopped, together with theswitching mechanism (50), and the humidity control function of thehumidity controller apparatus (10) is stopped.

However, during the ventilation/dehumidification mode and during theventilation/humidification mode, room ventilation must be continued evenwhen the humidity control function of the humidity controller apparatus(10) is brought to a stop. In other words, during theventilation/dehumidification mode and during theventilation/humidification mode, the exhaust fan (26) and the supply fan(25) are operated continuously so that the room is ventilatedcontinuously.

Embodiment 2 of Invention

A second embodiment of the present invention is a modification as aresult of modifying the configuration of the switching control part (73)of the controller (70) of the first embodiment. Here, differences of thepresent embodiment with the first embodiment are described.

The switching control means (73) of the present embodiment is configuredsuch that it performs switching of the operation of the refrigerantcircuit (60) and switching of the distribution routes of first andsecond air streams, which is the same as the first embodiment. However,as shown in FIGS. 14 and 15, the switching control part (73) of thepresent embodiment operates to perform switching of the operation of therefrigerant circuit (60) and switching of the distribution routes offirst and second air streams at different timing intervals. Theswitching control part (73) of the present embodiment constitutes aswitching control means.

The switching control part (73) of the present embodiment is capable oftwo different switching control operations and is configured such thatit selects either one of the two different switching control operationsdepending on the temperature of air streams taken into the casing (11)as first and second air streams.

More specifically, the switching control part (73) performs a firstswitching control operation for preswitching the distribution routes ofair streams within the casing (11) a predetermined length of time aheadof switching of the refrigeration cycle operation of the refrigerantcircuit (60) and a second switching control operation for switching thedistribution routes of air streams within the casing (11) after anelapse of a predetermined length of time since the switching of therefrigeration cycle operation of the refrigerant circuit (60). Morespecifically, the switching control part (73) performs a first switchingoperation if the temperature of a second air stream is higher than thetemperature of a first air stream on the way to the heat exchangers (61,62). On the other hand, if the temperature of a first air stream ishigher than the temperature of a second air stream on the way to theheat exchangers (61, 62), the switching control part (73) performs asecond switching operation.

Control Operation of Controller

The control operation of the controller (70) is described by makingreference to FIGS. 14 and 15. FIGS. 14 and 15 show variations,respectively, in the state of the switching mechanism (50), in thecapacity of the compressor (63), in the opening of the electricexpansion valve (65), in the adsorbent temperature of the first heatexchanger (61), and in the adsorbent temperature of the second heatexchanger (62), when the refrigeration cycle operation of therefrigerant circuit (60) is switched alternately in the order of a firstoperation, a second operation, a first operation, and a secondoperation.

The switching control part (73) of the present embodiment selectivelyperforms either one of a first switching control operation and a secondswitching control operation depending on the temperature of first andsecond air streams taken into the casing (11).

When a second air stream taken into the casing (11) has a highertemperature than a first air stream, the switching control part (73)performs a first switching control operation. Such a case corresponds tothe case where a circulation/dehumidification mode is carried out withthe room being cooled in the summertime and to the case where acirculation/humidification mode is carried out with the room beingheated in the wintertime.

As shown in FIG. 14, in the first switching control operation, theswitching mechanism (50) is switched a predetermined length of timeahead of switching of the refrigeration cycle operation of therefrigerant circuit (60). The first switching control operation isdescribed taking, as an example, a case where the operation of therefrigerant circuit (60) is switched at an interval of three minutes,i.e., a case where the switching cycle of the four-way selector valve(64) is three minutes. In this case, the switching control part (73)operates the switching mechanism (50) upon an elapse of for example twominutes and forty-five seconds since the four-way selector valve (64) isswitched, thereby to switch the distribution routes of first and secondair streams. And, the switching control part (73) operates the four-wayselector valve (64) upon an elapse of fifteen seconds since theswitching mechanism (50) is operated, thereby to switch therefrigeration cycle operation of the refrigerant circuit (60).

For example, in switching from a first refrigeration cycle operation toa second refrigeration cycle operation, the first heat exchanger (61)acting as a condenser is switched to act as an evaporator while, on theother hand, the second heat exchanger (62) acting as an evaporator isswitched to act as a condenser. When the switching control part (73)conducts a first switching control operation at that time, a first airstream of relatively low temperature is delivered to the first heatexchanger (61) slightly before the first heat exchanger (61) acting as acondenser switches to act as an evaporator. In addition, a second airstream of relatively high temperature is delivered to the second heatexchanger (62) before the second heat exchanger (62) acting as anevaporator switches to act as a condenser. As the result of this, thetemperature of the adsorbent provided in the first heat exchanger (61)falls lower and the temperature of the adsorbent provided in the secondheat exchanger (62) rises higher, when compared to a comparative examplein which the four-way selector valve (64) and the switching mechanism(50) are operated at the same time.

On the other hand, when the temperature of a first air stream taken intothe casing (11) is higher than the temperature of a second air stream,the switching control part (73) performs a second switching controloperation. Such a case corresponds to a case where aventilation/dehumidification mode is performed with the room beingcooled in the summertime and to a case where aventilation/humidification mode is carried out with the room beingheated in the wintertime.

As shown in FIG. 15, in the second switching control operation, theswitching mechanism (50) is switched after an elapse of a predeterminedlength of time since the refrigeration cycle operation of therefrigerant circuit (60) is switched. The second switching controloperation is described taking, as an example, a case where the operationof the refrigerant circuit (60) is switched at an interval of threeminutes, i.e., a case where the switching cycle of the four-way selectorvalve (64) is three minutes. In this case, the switching control part(73) does not operate the switching mechanism (50) at the point of timewhen the four-way selector valve (64) is switched, and the distributionroutes of air streams are maintained. Thereafter, the switching controlpart (73) operates the switching mechanism (50) upon an elapse of forexample fifteen seconds since the four-way selector valve (64) isswitched, thereby to switch the distribution routes of the first andsecond air streams. And, the switching control part (73) operates thefour-way selector valve (64) upon an elapse of two minutes andforty-five seconds since the switching mechanism (50) is operated,thereby to switch the refrigeration cycle operation of the refrigerantcircuit (60).

For example, in switching from a first refrigeration cycle operation toa second refrigeration cycle operation, the first heat exchanger (61)acting as a condenser is switched to act as an evaporator while, on theother hand, the second heat exchanger (62) acting as an evaporator isswitched to act as a condenser. When the switching control part (73)performs a second switching control operation at that time, a second airstream of relatively low temperature is continuously delivered to thefirst heat exchanger (61) for a while even after the first heatexchanger (61) acting as a condenser is switched to act as anevaporator. In addition, a first air stream of relatively hightemperature is continuously delivered to the second heat exchanger (62)for a while even after the second heat exchanger (62) acting as anevaporator is switched to act as a condenser. As the result of this, thetemperature of the adsorbent provided in the first heat exchanger (61)falls quickly and the temperature of the adsorbent provided in thesecond heat exchanger (62) rises quickly, when compared to a comparativeexample in which the four-way selector valve (64) and the switchingmechanism (50) are operated at the same time.

Effects of Embodiment 2

As described above, the present embodiment enables rapid variations inthe temperature of the adsorbent supported on the surface of each of theheat exchangers (61, 62) after switching of the operation of therefrigerant circuit (60). This makes it possible to reduce the time fromwhen the refrigeration cycle operation of the refrigerant circuit (60)is switched to when the adsorbent reaches a temperature capable ofallowing the adsorbent to effect sufficient moistureadsorption/desorption. Accordingly, in accordance with the presentembodiment, the amount of moisture being adsorbed on the adsorbent andthe amount of moisture being desorbed from the adsorbent will increase.And, as a result of such arrangement, it becomes possible to improve thehumidity control capability of the humidity controller apparatus (10).

Embodiment 3 of Invention

A third embodiment of the present invention is a modification as aresult of modifying the configuration of the capacity control part (71)of the controller (70) of the second embodiment. Here, differences ofthe present embodiment with the second embodiment are described.

As shown in FIG. 16, the capacity control part (71) of the presentembodiment constitutes a capacity control means for varying the capacityof the compressor (63) at the same cycle as the cycle at which therefrigeration cycle operation of the refrigerant circuit (60) isswitched.

More specifically, the capacity control part (71) of the presentembodiment performs a control operation for temporarily holding thecapacity of the compressor (63) at a low capacity level prior toswitching of the refrigeration cycle operation of the refrigerantcircuit (60) and then bringing the capacity of the compressor (63) backto a reference capacity level upon the switching of the refrigerationcycle operation of the refrigerant circuit (60). The capacity controlpart (71) performs the control operation every time the refrigerationcycle operation of the refrigerant circuit (60) is switched. Inaddition, the capacity control part (71) repeatedly performs the controloperation, independently of whether the switching control part (73) isin a first switching control operation or in a second switching controloperation.

The control operation of the capacity control part (71) is describedtaking as an example a case where the operation of the refrigerantcircuit (60) is switched at an interval of three minutes. In this case,the capacity control part (71) operates the compressor (63) at thereference capacity level from the time immediately after the four-wayselector valve (64) is switched. And, after an elapse of for example twominutes and thirty seconds since that switching, the capacity controlpart (71) reduces the capacity of the compressor (63) down to apredetermined low capacity level. Thereafter, the capacity control part(71) holds the capacity of the compressor (63) at the low capacity levelfor thirty seconds until the time the four-way selector valve (64) isagain switched. When the four-way selector valve (64) is switched, thecapacity control part (71) brings the capacity of the compressor (63)back to the original reference capacity level.

Here, a case in which the refrigerant circuit (60) makes a switch from afirst refrigeration cycle operation to a second refrigeration cycleoperation is described. During the first refrigeration cycle operation,moisture is desorbed from the adsorbent of the first heat exchanger (61)which becomes a condenser while, on the other hand, moisture present inan air stream is adsorbed on the adsorbent of the second heat exchanger(62) which becomes an evaporator. And, on the verge of completion of thefirst refrigeration cycle operation, moisture is not desorbed very muchfrom the adsorbent of the first heat exchanger (61) which becomes acondenser even when heated continuously, and moisture is not adsorbedvery much on the adsorbent of the second heat exchanger (62) whichbecomes an evaporator even when cooled continuously. In other words,even if the compressor (63) is continuously operated at a large capacitylevel to the verger of switching of the refrigeration cycle operation ofthe refrigerant circuit (60), the effect of increasing the amount ofdehumidification from the first air stream and the effect of increasingthe amount of humidification to the second air stream are not expectedvery much.

To cope with the above, the capacity control part (71) reduces thecapacity of the compressor (63) for cutting down the input to thecompressor (63), at the stage slightly prior to switching of theoperation of the refrigerant circuit (60) where any increase in theamount of dehumidification and the amount of humidification is no longerexpected. Accordingly, the present embodiment reduces the powerconsumption of the compressor (63) while maintaining the amount ofdehumidification and the amount of humidification obtained in thehumidity controller apparatus (10), thereby making it possible to aim ataccomplishing energy savings for the humidity controller apparatus (10).

In addition, when the capacity of the compressor (63) diminishes priorto switching of the operation of the refrigerant circuit (60), thecapability to heat adsorbent and the capability to cool adsorbent arereduced proportionally. Consequently, in comparison with a case wherethe capacity of the compressor (63) is kept constant, at the point oftime when the refrigeration cycle operation of the refrigerant circuit(60) is switched, the adsorbent temperature decreases in the heatexchanger (61, 62) that converts into an evaporator from a condenser,and increases in the heat exchangers (61, 62) that converts into acondenser from an evaporator. Therefore, in accordance with the presentembodiment, it becomes possible to reduce the time from when therefrigeration cycle operation of the refrigerant circuit (60) isswitched to when the adsorbent reaches a temperature capable of allowingthe adsorbent to effect sufficient moisture adsorption/desorption. As aresult, the humidity control capability of the humidity controllerapparatus (10) is improved to a further extent.

Embodiment 4 of Invention

A fourth embodiment of the present invention is a modification as aresult of modifying the configuration of the opening control part (72)of the controller (70) of the second embodiment. Here, differences ofthe present embodiment with the second embodiment are described.

As shown in FIG. 17, the opening control part (72) of the presentembodiment constitutes an opening control means for varying the openingof the electric expansion valve (65) at the same cycle as the cycle atwhich the refrigeration cycle operation of the refrigerant circuit (60)is switched.

More specifically, the opening control part (72) of the presentembodiment performs a control operation for gradually expanding theopening of the electric expansion valve (65) from the time slightlybefore the refrigeration cycle operation of the refrigerant circuit (60)is switched and then bringing the opening of the electric expansionvalve (65) back to a reference opening level upon the switching of therefrigeration cycle operation of the refrigerant circuit (60). Theopening control part (72) performs the control operation every time therefrigeration cycle operation of the refrigerant circuit (60) isswitched. In addition, the opening control part (72) repeatedly performsthe control operation, independently of whether the switching controlpart (73) is in a first switching control operation or in a secondswitching control operation.

The control operation of the opening control part (72) is describedtaking as an example a case where the operation of the refrigerantcircuit (60) is switched at an interval of three minutes. In this case,the opening control part (72) holds the opening of the electricexpansion valve (65) at the reference opening level from the timeimmediately after the four-way selector valve (64) is switched. And, theopening control part (72) starts increasing the opening of the electricexpansion valve (65) after an elapse of for example two minutes andthirty seconds since that switching. Thereafter, the opening controlpart (72) keeps increasing the opening of the electric expansion valve(65) for thirty seconds until the four-way selector valve (64) is againswitched. Upon the switching of the four-way selector valve (64), theopening control part (72) brings the opening of the electric expansionvalve (65) back to the original reference opening level.

As described in the description of the third embodiment, at the stageslightly prior to switching of the refrigeration cycle operation of therefrigerant circuit (60), any increase in the amount of dehumidificationand the amount of humidification is no longer expected. To cope withthis, the opening control part (72) increases the opening of theelectric expansion valve (65) in such a state. As the opening of theelectric expansion valve (65) increases, the high-low pressuredifference is reduced, thereby reducing power consumption in thecompressor (63) which compresses refrigerants. Accordingly, the presentembodiment makes it possible to cut down the amount of power consumed bythe compressor (63) while at the same time maintaining the amount ofdehumidification and the amount of humidification obtained in thehumidity controller apparatus (10), thereby making it possible to aim ataccomplishing energy savings in the humidity controller apparatus (10),as in the second embodiment.

In addition, as the opening of the electric expansion valve (65) isincreased prior to switching of the operation of the refrigerant circuit(60), the capability to heat adsorbent and the capability to cooladsorbent are reduced proportionally. This makes it possible to reducethe time from when the refrigeration cycle operation of the refrigerantcircuit (60) is switched to when the adsorbent reaches a temperaturecapable of allowing the adsorbent to effect sufficient moistureadsorption/desorption. As a result, the humidity control capability ofthe humidity controller apparatus (10) is improved further, as in thethird embodiment.

Modified Version of Embodiment 4

In the present embodiment, the capacity control part (71) of thecontroller (70) may be configured in the same way as in the thirdembodiment. In other words, the capacity control part (71) of thepresent embodiment may be so configured as to vary the capacity of thecompressor (63) at the same cycle as the cycle at which therefrigeration cycle operation of the refrigerant circuit (60) isswitched. And, in the present modified version, both the controlling ofthe opening of the electric expansion valve (65) by the opening controlpart (72) and the controlling of the capacity of the compressor (63) bythe capacity control part (71) are performed in response to switching ofthe operation of the refrigerant circuit (60).

Embodiment 5 of Invention

A fifth embodiment of the present invention is a modification as aresult of modifying the configuration of the capacity control part (71)of the controller (70) of the second embodiment. Here, differences ofthe present embodiment with the second embodiment are described.

As shown in FIG. 18, the capacity control part (71) of the presentembodiment constitutes a capacity control means for varying the capacityof the compressor (63) at the same cycle as the cycle at which therefrigeration cycle operation of the refrigerant circuit (60) isswitched.

More specifically, the capacity control part (71) of the presentembodiment performs a control operation for holding the capacity of thecompressor (63) at a higher capacity level than the reference capacitylevel until a predetermined length of time elapses from the timeimmediately after switching of the operation of the refrigerant circuit(60) and then bringing the capacity of the compressor (63) back to thereference capacity level and holding it there. The capacity control part(71) performs the control operation every time the refrigeration cycleoperation of the refrigerant circuit (60) is switched. In addition, thecapacity control part (71) repeatedly performs the control operation,independently of whether the switching control part (73) is in a firstswitching control operation or in a second switching control operation.

The control operation of the capacity control part (71) is describedtaking as an example a case where the refrigeration cycle operation ofthe refrigerant circuit (60) is switched at an interval of threeminutes. In this case, the capacity control part (71) holds the capacityof the compressor (63) at a greater capacity level than the referencecapacity level for for example thirty seconds from the time immediatelyafter switching of the four-way selector valve (64). Thereafter, thecapacity control part (71) reduces the capacity of the compressor (63)down to the reference capacity level and then keeps the capacity of thecompressor (63) constant for two minutes and thirty seconds until thetime the four-way selector (64) is switched next.

As described above, in order for the humidity controller apparatus (10)to exhibit sufficient humidity control capabilities, desirably theadsorbent temperature is rapidly decreased in the heat exchanger (61,62) that has converted into an evaporator from a condenser and theadsorbent temperature is rapidly increased in the heat exchanger (61,62) that has converted into a condenser from an evaporator.

To this end, in the present embodiment the capacity control part (71) ofthe controller (70) performs the above-described control operation sothat the compressor (63) is temporarily operated at a greater capacitylevel immediately after the operation of the refrigerant circuit (60) isswitched. In other words, the capacity of the compressor (63) istemporarily increased by the control operation of the capacity controlpart (71) when the temperature of the adsorbent supported on the surfaceof each of the heat exchangers (61, 62) should be varied rapidly, i.e.,immediately after switching of the operation of the refrigerant circuit(60).

As a result of such arrangement, for example during switching from afirst refrigeration cycle operation to a second refrigeration cycleoperation, the temperature of the adsorbent falls quickly in the firstheat exchanger (61) which has converted into an evaporator from acondenser while, on the other hand, the temperature of the adsorbentrises quickly in the second heat exchanger (61) which has converted intoa condenser from an evaporator. Therefore, in accordance with thepresent embodiment, it becomes possible to reduce the time from when therefrigeration cycle operation of the refrigerant circuit (60) isswitched to when the adsorbent reaches a temperature capable of allowingthe adsorbent to effect sufficient moisture adsorption/desorption. As aresult, the humidity control capability of the humidity controllerapparatus (10) is improved to a further extent.

Embodiment 6 of Invention

A sixth embodiment of the present invention is a modification as aresult of modifying the configuration of the opening control part (72)of the controller (70) of the second embodiment. Here, differences ofthe present embodiment with the second embodiment are described.

As shown in FIG. 19, the opening control part (72) of the presentembodiment constitutes an opening control means for varying the openingof the electric expansion valve (65) at the same cycle as the cycle atwhich the refrigeration cycle operation of the refrigerant circuit (60)is switched.

More specifically, the opening control part (72) of the presentembodiment once reduces the opening of the electric expansion valve (65)immediately after the operation of the refrigerant circuit (60) isswitched and then increases it again. Thereafter, the opening controlpart (72) holds the opening of the electric expansion valve (65) at areference opening level until the next operation switching. In otherwords, the opening control part (72) performs a control operation forcontinuously reducing the opening of the electric expansion valve (65)from the time immediately after switching of the refrigeration cycleoperation of the refrigerant circuit (60) and then reopening theelectric expansion valve (65) when the opening of the electric expansionvalve (65) reaches a predetermined opening level so that the opening ofthe electric expansion valve (65) is brought back to the originalopening level. The opening control part (72) performs the controloperation every time the refrigeration cycle operation of therefrigerant circuit (60) is switched. In addition, the opening controlpart (72) repeatedly performs the control operation, independently ofwhether the switching control part (73) is in a first switching controloperation or in a second switching control operation.

In the present embodiment, the opening control part (72) temporarilyreduces the opening of the electric expansion valve (65) at the stageimmediately after switching of the refrigeration cycle operation of therefrigerant circuit (60) where rapid heating or cooling of the adsorbentis required. As the opening of the electric expansion valve (65)decreases, the high-low pressure difference in the refrigeration cycleincreases, and the temperature of refrigerant condensation rises whileon the other hand the temperature of refrigerant evaporation drops.Accompanied with this, the temperature of the adsorbent rises quickly inthe heat exchanger (61, 62) switched to a condenser while on the otherhand the temperature of the adsorbent drops quickly in the heatexchanger (61, 62) switched to an evaporator. Therefore, in accordancewith the present embodiment, it becomes possible to reduce the time fromwhen the refrigeration cycle operation of the refrigerant circuit (60)is switched to when the adsorbent reaches a temperature capable ofallowing the adsorbent to effect sufficient moistureadsorption/desorption. As a result, the humidity control capability ofthe humidity controller apparatus (10) is improved to a further extent.

Modified Version of Embodiment 6

In the present embodiment, the capacity control part (71) of thecontroller (70) may be configured in the same way as in the fifthembodiment. In other words, the capacity control part (71) of thepresent embodiment may be configured such that the capacity of thecompressor (63) varies at the same cycle as the cycle at which therefrigeration cycle operation of the refrigerant circuit (60) isswitched. And, in the present modified version, both the controlling ofthe opening of the electric expansion valve (65) by the opening controlpart (72) and the controlling of the capacity of the compressor (63) bythe capacity control part (71) are performed in response to switching ofthe operation of the refrigerant circuit (60).

Other Embodiments of Invention

In each of the third to sixth embodiments, the switching control part(73) is configured such that the operation of the refrigerant circuit(60) and the distribution routes of first and second air streams areswitched at different timing intervals; however, the switching controlpart (73) may be configured in the same way as the one described in thefirst embodiment. In other words, the switching control part (73) may beconfigured such that the operation of the refrigerant circuit (60) andthe distribution routes of first and second air streams are switched atthe same timing interval.

In addition, each of the aforesaid embodiments is an example as a resultof application of the present invention to the humidity controllerapparatus (10) of the type in which the heat exchanger (61, 62) with anadsorbent supported on its surface constitutes an adsorption unit. It,however, should be noted that the scope of application of the presentinvention is not limited to such a type of the humidity controllerapparatus (10). In other words, the present invention may be applied toa humidity controller apparatus as disclosed in Patent Document III,e.g., a type of humidity controller apparatus in which each adsorptionunit is formed by an adsorption element for bringing air streams flowingthrough a great number of air passages formed therein into contact withan adsorbent so that a first air stream is dehumidified in theadsorption element and a second air stream heated is supplied to theadsorption element for regenerating the adsorbent.

INDUSTRIAL APPLICABILITY

As has been described above, the present invention is useful forhumidity controller apparatuses which regulate the humidity of air.

1. A humidity controller apparatus which takes in a first air stream anda second air stream and supplies to an indoor space either the first airstream dehumidified or the second air stream humidified, wherein: thehumidity controller apparatus comprises a first adsorption unit and asecond adsorption unit, each of the first and second adsorption unitshaving a respective adsorbent which is brought into contact with air,the humidity controller apparatus is configured to perform, repeatedlyalternately at a predetermined switching time interval, a firstoperation in which the second air stream is humidified as a result ofregeneration of the adsorbent of the first adsorption unit while,simultaneously, the first air stream is dehumidified in the secondadsorption unit and a second operation in which the second air stream ishumidified as a result of regeneration of the adsorbent of the secondadsorption unit while, simultaneously, the first air stream isdehumidified in the first adsorption unit, and the humidity controllerapparatus is provided with interval set means for setting thepredetermined switching time interval depending on the load of thehumidity controller apparatus.
 2. The humidity controller apparatus ofclaim 1 wherein the interval set means is configured to set thepredetermined switching time interval such that the set value of thepredetermined switching time interval decreases as the load of thehumidity controller apparatus increases.
 3. The humidity controllerapparatus of claim 1 wherein: the humidity controller apparatuscomprises a refrigerant circuit in which a plurality of heat exchangerseach supporting on its surface a respective adsorbent are connected, therefrigerant circuit allowing for switching between a first refrigerationcycle operation in which the first heat exchanger becomes a condenserwhile the second heat exchanger becomes an evaporator and a secondrefrigeration cycle operation in which the second heat exchanger becomesa condenser while the first heat exchanger becomes an evaporator, andthe refrigerant circuit performs a first refrigeration cycle operationduring the first operation while, on the other hand, the refrigerantcircuit performs a second refrigeration cycle operation during thesecond operation, and the first heat exchanger and the second heatexchanger constitute, respectively, a first adsorption unit and a secondadsorption unit.
 4. The humidity controller apparatus of claim 3comprising: a switching mechanism for switching of the distributionroutes of the first and second air streams in response to interswitchingbetween the first operation and the second operation, and switchingcontrol means for performing a control operation so that the switchingmechanism preswitches the distribution routes of air streams apredetermined length of time ahead of switching of the operation of therefrigerant circuit, when the second air stream has a higher temperaturethan the first air stream on the upstream side of the heat exchangers.5. The humidity controller apparatus of claim 3 comprising: a switchingmechanism for switching of the distribution routes of the first andsecond air streams in response to interswitching between the firstoperation and the second operation, and switching control means forperforming a control operation so that the switching mechanismpreswitches the distribution routes of air streams a predeterminedlength of time ahead of switching of the operation of the refrigerantcircuit, when the second air stream has a higher temperature than thefirst air stream on the upstream side of the heat exchangers.
 6. Thehumidity controller apparatus of claim 3 wherein: a compressor, disposedin the refrigerant circuit, is configured to be variable in capacity,and capacity control means is provided which varies the capacity of thecompressor at the same cycle as the cycle at which the operation of therefrigerant circuit is switched.
 7. The humidity controller apparatus ofclaim 3 wherein: a refrigerant expansion mechanism, disposed in therefrigerant circuit, is formed by an expansion valve which is variablein opening, and opening control means is provided which varies theopening of the expansion valve at the same cycle as the cycle at whichthe operation of the refrigerant circuit is switched.